I've just looked up the price of smalti. Smalti are the bright little cubes you use to make mosaics. I'd call them tesserae, but they are smalti to Orsoni, the Venetian company that makes them. Lucio Orsoni has just popped over to London for a chat with Archbishop Vincent Nichols about covering the inside of the domes of Westminster Cathedral with mosaics, as the architect intended a century ago.
This is a big job. The area to be covered is greater than that of St Mark's in Venice. At Westminster the three bays of the nave alone are each 60ft square (in imperial), giving a total area of roughly 1,000 square metres (in European). You get about 10,000 smalti to the square metre. Mr Orsoni thinks that gold would be a nice background colour, and, going by his online price list, that works out at more than 1,000 euros a square metre, not counting labour or grouting.
It would be wonderful to finish the job at Westminster. There are two dim arguments against it and half a good one. The first dim argument is that the money could be spent on the poor. But it wouldn't be. This is not a zero-sum game. Money in London is spent on things like those glowing text displays on bus shelters that tell you how long it is until the next bus comes. It is spent on fitted kitchens with cupboards that don't slam with a bang, on gym subscriptions and television licences, on ready meals and pet insurance. None of those things lasts long, and the poor don't come into it. Anyway, the poor like looking at mosaics, too.
The second dim argument is put by Nikolaus Pevsner and architectural snobs. "The interior is without doubt one of the most moving of any church in London," they say, "due to the fact that it is unfinished." It is true that on a dark winter's afternoon, with the soot-blackened brickwork lost in gloom, the space is beautiful. But ruins such as Rievaulx are beautiful, too. Does that mean we should engineer more ruins?
The half-good argument is that new mosaics would be badly designed. The last time they tried to cover a large area – the apse half-dome, in 1934 – it was so bad that it all had to be chipped off again. This is the argument of fainéant pessimists, which is why it half appeals to me.
But Westminster Cathedral is built in the Byzantine mode. When Vladimir, Grand Prince of Kiev, sent envoys to Constantinople in 987 to see whether the Byzantine form of worship would suit the land of the Rus, they reported, after seeing the liturgy beneath its domes of golden mosaic: "We no longer knew whether we were in heaven or on earth."